adding onclick code example
Example 1: javascript onclick
var myElem = document.getElementByID('ElemID');
myElem.onclick = function() {
//do stuff
}
Example 2: button click function in js
<script>
$(document).ready(function(){
$('#MyButton').click(function(){
CapacityChart();
});
});
</script>
<input type="button" value="Capacity Chart" id="MyButton" >